The Food and Drug Administration can enact policies reducing the nicotine content of cigarettes to non-addictive levels, which could significantly improve public health. It is imperative to examine how nicotine reduction in cigarettes may impact closely related health behaviors, particularly alcohol use. Alcohol use is a leading preventable cause of morbidity and death in the United States and may be causally related to cigarette use among smokers. As a result, policies reducing the nicotine content in cigarettes could affect alcohol use. The proposed study will be the first clinical trial to examine how smoking very low nicotine content (VLNC) cigarettes impacts alcohol-related outcomes. The study will determine if smoking VLNC cigarettes impacts alcohol use, binge drinking, and dependence symptoms and if the effects differ between men and women. Data will be collected as part of a multi-site randomized clinical trial, in which participants (N=840) will be randomly assigned to smoke cigarettes of varying nicotine yields at (i.e., 0.8 mg) or below (i.e., 0.03 mg, 0.07 mg, 0.13 mg, or 0.25 mg) the yields typically sold in the U.S.. Over a 6-week period, participants will report daily cigarette using an Interactive Voice Response (IVR) system and daily alcohol use and non-study tobacco use will be assessed with a weekly administered timeline follow back questionnaire. Alcohol dependence symptoms will be assessed at baseline and Week 6 and nicotine biomarkers indicative of total nicotine exposure will be collected at baseline, Week 2, and Week 6. The study aims will be tested with the time- varying effects model, which will utilize the intensive longitudinal data to estimate the effects of smoking VLNC cigarettes on same-day alcohol use and binge drinking levels and explore if the associations change over time. The impact of smoking VLNC cigarettes on alcohol dependence symptoms will be examined using regression models. The impact of nicotine exposure from non-study tobacco products on study findings will be evaluated. Finally, gender differences will be described. The results will have important public health implications as the FDA makes decisions about nicotine regulations in the United States. Furthermore, the study will make valuable contributions to theory by examining if the relationship between cigarette and alcohol use is attributable to nicotine and exploring contexts that may alter the relationship.